Device for discriminating color coded articles

ABSTRACT

A conventional color sensitive device produces a train of color signals responsive to rays incident thereon from an article having one of predetermined color codes. A pulse generator produces a pulse responsive to each of the color signals. A memory device produces a set of parallel signals responsive to the color signals and the pulses. Responsive to the parallel signals, a discrimination device produces a signal representative of the presence of the article having one of the color codes.

United States Patent Ebukuro et al. July 8, 1975 [54] DEVICE FOR DISCRIMINATING COLOR 3,584,779 6/1971 Kessler et al 235/61.11 E CO ARTICLES 3,637,993 1/1972 Christie et a1 235/61.11 E

[75] Inventors: glnfioufETblliklll? Tomoyuki Isono, Primary Examiner Daryl W. Cook 0t 0 0 apan Attorney, Agent, or Firm-Sughrue, Rothwell, Mion, [73] Assignee: Nippon Electric Company, Limited, ml & Macpea Tokyo, Japan 22 Filed: Dec. 27, 1973 [57] ABSTRACT A conventional color sensitive device produces a train [21] Appl' 428973 of color signals responsive to rays incident thereon from an article having one of predetermined color [52] US. Cl. 235/6l.l1 E; 250/566 codes. A pulse generator produces a pulse responsive [51] Int. Cl. 606k 7/10; G08c 9/06 to h f he l r signals. A memory device pro- [58] Field of Search 235/61.11 E; 340/ 146.3 K, duces a set of parallel signals responsive to the color 340/1463 B; 250/555, 566; 209/1l1..6 signals and the pulses. Responsive to the parallel signals, a discrimination device produces a signal repre- [56] References Cited sentative of the presence of the article having one of UNITED STATES PATENTS the Color Codes- 3,417,231 12/1968 Stites et a1 235/61.11 E 5 Claims, 3 Drawing Figures [R] 015cm OUTPUT [B] 1 R 1' [w] MEMORY MINATION W 0 PHOTO- i 6 COLOR r -38 6" ELECTRIC DETECT TRANSD. l8 B 1 -mn- I PULSE ,36 ,37 GEN H (5. I SWITCH DELAY L 5C 1 DEVICE FOR DISCRIMINATING COLOR CODED ARTICLES BACKGROUND OF THE INVENTION This invention relates to a device for discriminating color coded articles from other articles. The device is useful in selecting airmails in automatic mail handling systems, in detecting articles having deficiencies in colors and their dispositions in manufacture, in sorting various color coded articles, and in other arts of handling articles having areas colored in a predetermined number of colors and arranged in predetermined orders.

To speak of the automatic mail handling systems, it is one of important functions to sort airmails from other mail articles. It has been conventional to select the airmails by detecting the colors of the relatively highpriced postage stamps usually attached to the airmails. This, however, results in mis-selection of some of airmails on which low-priced postage stamps used in ordinary mails were attached.

In general, there has been no device available for discriminating articles having predetermined color codes from other articles.

SUMMARY OF THE INVENTION It is therefore an object of this invention to provide a device for discriminating articles having predetermined color codes from other articles.

A subordinate object of this invention is to provide a device for discriminating specific mails, such as air mails, from other mail articles without resorting to detection of the postage stamps attached to mails.

Specific articles to be discriminated by a device according to this invention have predetermined color codes. The color codes comprise areas, each colored in one ofa predetermined number of colors, with the colored areas arranged in predetermined orders, respectively. The device comprises a conventional color sensitive device responsive to rays incident thereon from the colored areas of each article having one of the color codes for producing a train of color signals representative of the respective colors of the above-mentioned one color code. In order to produce the color signals in a train, the color sensitive device may manually be moved adjacent to the articles to be discriminated. In an automatically operable device, the articles to be discriminated are pereferably fed in front of the color sensitive device so that the color sensitive device may successively scan the articles. In accordance with this invention, the device for discriminating color coded articles comprises a pulse generator responsive to each of the color signals for producing a pulse. The device further comprises memory means responsive to the color signals and the pulses produced in response to the color signals for producing a set of parallel signals. The device still further comprises discrimination means responsive to the parallel signals for producing a signal representative of presence of the article having the above-mentioned one color code. The color may be one of the achromatic colors.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a block diagram of an embodiment of this invention;

FIG. 2 schematically shows an example of a portion of the embodiment depicted in FIG. 1; and

FIG. 3 similarly shows another example of the portion illustrated in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS At first, an embodiment of this invention as applied to discrimination of airmails from other mail articles will be described by way of example. An airmail envelope has areas colored in a predetermined number of colors. The colored areas are arranged along the four edges of its front surface in one of predetermined orders. The colored areas may differ in color and width from envelope to envelope but may be said to provide predetermined color codes to the airmails. It is to be noted here that envelopes used in mails other than the airmails may have ornametal patterns on their front surfaces but that these patterns seldom coincide with the color codes of the airmails so that the mails having the predetermined color codes may be looked upon airmails. For simplicity, it is assumed here that the colors used in the airmail envelopes as the codes are the background color called herein white for brevity, red, and blue and that the colored areas are arranged with a white area interposed between red and blue areas. In this connection, it should be pointed out that an automatic mail handling system includes a device for feeding mail articles one after another as described in US. Pat. No. 3,745,527 issued to Shoichiro Yoshimura, Rinzou Ebukuro, and Tomoyuki Isono, with one of the edges of each mail moving along a predetermined path.

Referring now to FIG. 1, a device for detecting the airmails among mail articles (not shown) fed one by one along a feed route 10 with aligned edges running along a predetermined path, comprises a conventional color sensitive device generally shown at 11, which may be a combination of the filters 31 through 33, phototubes 36 through 38, and color detector 49 described in the above-mentioned patent. More particularly, the color sensitive device 11 comprises a photoelectric transducer device 12 responsive to rays incident thereon successively from the aligned edge portions of the mail articles. Preferably, the mail articles are illuminated by a lamp 15. When an airmail is fed in front of the transducer device 12, the colored areas of the airmail envelope send red rays (R), white rays (W), and blue rays (B) in one of the four orders: (I): (R), (W), (W); and (4): (W), (R), (W), (B). The transducer device 12 comprises a condenser lens (not shown), means (notshown), such as one or more half-silvered mirrors, for splitting the rays having passed through the lens into a plurality of rays travelling along their respective paths, and a like number of phototubes (not shown) of specific spectral sensitivities placed in the respective paths of rays. Instead of the phototubes of the specific spectral sensitivities, use may be made of a plurality of optical filters disposed in the respective paths and phototubes of equal or different spectral sensitivities. Alternatively, dichroic filters may be used in place of the half'silvired mirrors and the optical filters. In the example being illustrated, the transducer device 12 produces responsive to the rays incident thereon from one of the colored areas one or a combination of a first signal representative of red R, a second signal representative of green G, and a third signal representative of blue B. The color sensitive device 11 further comprises three amplifiers 16, 17, and 18 adjusted to produce equalized signals representative of the three primary colors R, G, and B in response to the first through third signals. The adjustment may be carried out by placing a sheet of photometrically white paper in front of the transducer device 12 until the amplifiers 16 through 18 produce output signals of equal level. The color sensitive device 11 still further comprises a color detector 19 having a plurality of output terminals and responsive to the equalized signals for producing a train of color signals, which are a red" signal [R], a blue signal [B], and a white" signal [W] produced at three of the output terminals in one of the four orders mentioned above in the case being illustrated. It is to be noted here that the color detector 49 described in the above-referenced patent includes the above-mentioned amplifiers 16 through 18. Alternatively, the color detector 19 may process the equalized signals to produce the color signals in the manner revealed in Japanese Patent Application No. Syo 4l-7 l 524 or Syo 39-4895 l As a further alternative, it is possible under the circumstances where the colors of the color codes are limited to three, such as generally red, generally blue, and generally white, to produce the color signals [R], [B], and [W] with a color detector 19 of very simple construction, by distinguishing the generally blue color from the generally white color which may be somewhat blue.

Referring further to FIG. 1, the device according to the present invention further comprises a pulse generates 20 responsive to the color signals [R], [B], and [W] for producing a pulse Sp each time the color signal appears, and a memory device 21 responsive to the color signals and the pulses Sp produced in response to the color signals for producing a set of parallel signals. The pulse generator 20 may comprise a plurality of differentiating circuits (not shown) supplied with the respective color signals to produce pulses at the leading and the trailing edges of each color signal, diodes (not shown) connected with a predetermined polarity to the respective differentiating circuits to gate those pulses which are produced only at the leading or trailing edges of the color signals, pulse shaping circuits (not shown) connected to the respective diodes to shape the gated pulses, and an OR gate (not shown) connected to the pulse shaping circuits for producing the pulses Sp. As will become clear later, the pulses Sp serve to make the device according to the present invention discriminate airmails having color codes of different colored areas from other mail articles. Preferably, the pulse generator 20 further comprises a delay circuit (not shown) for giving a slight delay to the output pulses of the OR gate so that the pulses Sp may appear when the approximate middle points of the colored areas are scanned. The delay circuit may be a monostable multivibrator.

Turning to FIG. 2, an example of the memory device 21 comprises an encoder 22 responsive to each of the color signals [R], [B], and [W] for producing a coded signal representative of the color represented by the color signal, a shift register 23 responsive to the coded signal and the pulse Sp for producing a set of parallel coded signals, and a plurality of decoders 24 responsive to the parallel coded signals for producing the afore mentioned parallel signals. Inasmuch as the colors are three in number, use may be made of a coded signal of two bits E and E For example, these bits E and E become logic 0 and l to represent red, logic I and O to represent blue, both logic 1 to represent white, and both logic 0 for other colors. The encoder 22 may be Composed of gate circuits (not shown) in the manner readily occur to those skilled in the wired logics because the color signals do not simultaneously appear. It will now be understood that there is one-to-one correspondence between the pulses Sp and the respective combinations E, and E of the coded signals and that the encoder 22 produces logic 0 coded signals when the color sensitive device 11 scans ordinary mails. Preferably, the coded signals are supplied to the shift register 23 through an AND gate circuit 25 controlled by the pulses Sp produced when the substantial middle points of the colored areas are scanned. The color detector 19 shown in FIG. 1 may happen to produce an erroneous color signal [R], [B], or [W] in response to a spurious colored area, such as the letters described on the front surface of the mail being scanned. Inasmuch as the spurious areas are generally smaller in width than the areas of the color codes, the coded signal produced in response to the erroneous color signal will not appear simultaneously with the delayed pulse produced in response to the erroneous color signal. In the example being illustrated, the shift register 23 may be a fourstage two-bit shift register in which the two-bit coded signal E, and E is shifted from stage to stage by the pulses Sp. After four colored areas have been scanned, the shift register 23 produces at the respective stages a set of parallel coded signals, each consisting oftwo bits. When the colored areas of an airmail are scanned, three of the decoders 24 connected to each stage of the shift register 23 decode one of the parallel coded signals supplied thereto so that the decoders 24 produce four parallel signals R W B W W B W R 8,, W R W or W,, R W 8,, each from the pertinent one of the three decoders. When the mail being scanned is not an airmail, the decoders 24 do not produce four parallel output signals. Each of the decoders 24 may be composed of gate circuits (not shown) as will easily be understood by those skilled in the wired logics.

Turning back to FIG. 1 and referring further to FlG. 2, the device according to the present invention comprises a discrimination device 30 responsive to the parallel signals for producing a signal representative of detection of an airmail. In the example being illustrated, the discrimination device 30 comprises four four-input AND gates 31, 32, 33, and 34 connected to the decoders 24 in such a manner that a logic product signal is produced from the pertinent one, when a set of four parallel signals R W B;,, W,; W,, B W R B W R W or W,, R W 8,, are produced by the decoders 24. The discrimination device 30 further comprises an OR gate 35 connected to the AND gates 31 through 34 so as to produce an output signal of the device according to this invention when one of the AND gates 31 through 34 produces a logic product signal.

Further referring to FIG. 1, the device according to the present invention preferably comprises a photoelectric switch 36 placed adjacent to the feed route 10 upstream of the color sensitive device 11 and a delay circuit 37, responsive to an output signal produced by the photoelectric switch 36 when the leading edge of a mail article enters the field of the photoelectric switch 36, for producing a mail presence signal Sc that lasts from the time when the mail article enters the field of the color sensitive device 11 until the time at which the mail article tends to go out of the color sensitive device field. The mail presence signal Sc is supplied to an AND gate 38 depicted with broken lines to open-the same for a predetermined time interval so that the pulses Sp may be produced only while a predetermined area of the mail article is scanned. The mail presence signal Sc may further be supplied to another AND gate 39 shown in FIG. 2 with broken lines toensure produc tion of the coded signals, each having two bits'E, and E in the example being illustrated, within the predetermined time interval. Alternatively, the mail presence signal Sc may be supplied to the color detector 19 as symbolized by a broken line connection to restrict in effect the area of scan.

In connection with the example illustrated with reference to FIG. 2, it may be mentioned here that two of the decoders 24 for the parallel coded signals W, and W may be dispensed with when the presence ofa white area between a red and blue area is taken into consideration of the conditions for discrimination. Likewise, it is possible to dispense with the fourth stage of the shift register 23 in view of the predetermined orders of the colored areas. Further, use may be made ofa shift reg-' ister 23 having only two stages in consideration of the fact that a white area is always contiguous to a red and a blue area. It should, however, be noted that such simplifications of the device according to the present invention may result in misrecognition of airmails. On the contrary, it will be easy for those skilled in the art to adapt the embodiment thus far described to discrimination of airmails enclosed with airmails envelopes, each having a generally green area instead of the blue area, a generally green and a generally yellow area instead of the red and blue areas, or a continuation of a red, a blue, and a white area.

Referring now to FIG. 3, another example of the memory device 21 comprises three two-input AND gates 41, 42, and 43, supplied simultaneously with the pulse Sp and the color signals [R], [B], and [W], respectively, for producing a logic product signal in the presence of one of the color signals. The pulse Sp serves as a sampling pulse which may be supplied similarly to the AND gates (not shown) of the encoder 22 shown in FIG. 2. The memory device 21 further comprises flip-flops 46, 47, and 48 set by the logic product signals produced in the presence of the red, blue, and white signals, respectively. The flip-flops 46 through 48 are reset by a reset pulse RES produced, for example, at the leading edge of the mail presence signal Sc. It will be understood from FIG. 3 that the flip-flop 48 connected to the AND gate 43 for the white signal operates as a binary counter. Inasmuch as the white rays (W) appear twice in each of the four orders mentioned above, this flip-flop 48 is reset to turn the NOT output W to logic 1 when four colored areas have been scanned. This output W and set outputs r and b of the other flipflops 46 and 47 serve as the afore-mentioned parallel signals. Another example of the discrimination device 30 comprises a three-input AND gate 51 supplied with the parallel signals for producing a logic product signal and a temporary memory, such as flip-flop 52, for storing the logic product signal.

In operation, it is assumed that an airmail provides a pattern of the order l mentioned above. It is also assumed that the flip-flops 46 through 48 are reset at first to produce outputs r, b, and Wwhich are logic 0, O, and 1, respectively. Responsive to the red signal [R], the output r of the flip-flop 46 becomes logic 1. Responsive to the first white signal [W], the output W of the flipflop 48 turns to logic 0. Responsive to the blue signal [B], the output I; of the'flip-flop 47 turns to logic 1 Resporisive to the second white signal [W], the output W of the flip-flop 48 returns to logic 1. The AND gate 51 therefore produces. a logic product signal of logic I to make the temporarymemory 52 produce a signal representative of detection of an airmail.

Besides the examples described in the opening paragraph of the instant specification, a device, according to the present invention is applicable to discrimination of express delivery mails from other mail articles if the express delivery mails are provided with specific color codes. As an example of sorting various color coded articles, it is possible with the use of an automatic assembly machine equipped with a device according to the present invention to deliver various color coded resistors to respective locations of electronic apparatus according to the resistances. An article to be detected may have two or more of the predetermined color codes.

What is claimed is:

1. A device for discriminating articles having predetermined color codes from other articles, said codes comprising areas, each colored in one of a predetermined number of colors, with the colored areas arranged in predetermined orders, said device including color sensitive means responsive to rays incident thereon from the colored areas of each article having one of said codes for producing a train of color signals representative of the respective colors of the areas of said one code, wherein the improvement comprises:

a pulse generator responsive to each of said color signals-for producing a pulse.

an encoder responsive to each of said color signals for producing a coded signal representative of the color represented by said each color signal,

shift register means responsive to said coded signal and to the pulse produced in response to the color signal responsive to which said coded signal is produced, for producing a set of parallel coded signals,

a plurality of decoders responsive to said parallel coded signals for producing said parallel signals, and

discrimination means responsive to said parallel signals for producing a signal representative of said each article.

2. A device as claimed in claim 1, wherein said discrimination means comprises:

a plurality of AND gates, each responsive to the parallel signals produced responsive to a predetermined number of the colored areas for producing a logic product signal and an OR gate responsive to said logic product signal for producing the signal representative of the article having said one code.

3. A device as claimed in claim 1, further comprising:

article detection means responsive to rays incident thereon from a predetermined number of said colored areas for producing an article presence signal and gate means enabled by said article presence signal for making said memory means produce said parallel signals only while said rays are incident on said color detection means from said predetermined number of the colored areas.

4. A device for discriminating articles having predetermined color codes from other articles, said codes comprising areas, each colored in one of a predetermined number of colors, with the colored areas arranged in predetermined orders, said device including color sensitive means responsive to rays incident thereon from the colored areas of each article having one of said codes for producing a train of color signals representative of the respective colors of the areas of said one code. wherein the improvement comprises:

a pulse generator responsive to each of said color signals for producing a pulse,

a plurality of AND gates responsive to said pulses and the respective ones of said color signals for producing logic product signals, respectively, said logic product signals being representative of the respective colors respresented by said color signals,

a plurality of flip-flops set by the respective ones of said logic product signals to produce said parallel signals; and

discrimination means responsive to said parallel signals for producing a signal representative of said each article.

A device as claimed in claim 4, wherein said discrimination means comprises:

an AND gate responsive to the parallel signals proresentative of the article having said one code. =l l l 

1. A device for discriminating articles having predetermined color codes from other articles, said codes comprising areas, each colored in one of a predetermined number of colors, with the colored areas arranged in predetermined orders, said device including color sensitive means responsive to rays incident thereon from the colored areas of each article having one of said codes for producing a train of color signals representative of the respective colors of the areas of said one code, wherein the improvement comprises: a pulse generator responsive to each of said color signals for producing a pulse, an encoder responsive to each of said color signals for producing a coded signal representative of the color represented by said each color signal, shift register means responsive to said coded signal and to the pulse produced in response to the color signal responsive to which said coded signal is produced, for producing a set of parallel coded signals, a plurality of decoders responsive to said parallel coded signals for producing said parallel signals, and discrimination means responsive to said parallel signals for producing a signal representative of said each article.
 2. A device as claimed in claim 1, wherein said discrimination means comprises: a plurality of AND gates, each responsive to the parallel signals produced responsive to a predetermined number of the colored areas for producing a logic product signal and an OR gate responsive to said logic product signal for producing the signal representative of the article having said one code.
 3. A device as claimed in claim 1, further comprising: article detection means responsive to rays incident thereon from a predetermined number of said colored areas for producing an article presence signal and gate means enabled by said article presence signal for making said memory means produce said parallel signals only while said rays are incident on said color detection means from said predetermined number of the colored areas.
 4. A device for discriminating articles having predetermined color codes from other articles, said codes comprising areas, each colored in one of a predetermined number of colors, with the colored areas arranged in predetermined orders, said device including color sensitive means responsive to rays incident thereon from the colored areas of each article having one of said codes for producing a train of color signals representative of the respective colors of the areas of said one code, wherein the improvement comprises: a pulse generator responsive to each of said color signals for producing a pulse, a plurality of AND gates responsive to said pulses and the respective ones of said color signals for producing logic product signals, respectively, said logic product signals being representative of the respective colors respresented by said color signals, a plurality of flip-flops set by the respective ones of said logic product signals to produce said parallel signals; and discrimination means responsive to said parallel signals for producing a signal representative of said each article.
 5. A device as claimed in claim 4, wherein said discrimination means comprises: an AND gate responsive to the parallel signals produced responsive to a predetermined number of the colored areas for producing a logic product signal and a temporary memory responsive to the last-mentioned logic signal for producing the signal representative of the arTicle having said one code. 